1. Field of the Invention
The present invention relates to an image processing apparatus for a scanning endoscope that scans a subject with light to acquire an image.
2. Description of the Related Art
In recent years, endoscopes have been widely used in a medical field and the like. Various techniques for reducing a diameter of an insertion portion inserted to a subject are also proposed. An example of the techniques includes a scanning endoscope apparatus.
A conventional example of the scanning endoscope apparatus disclosed in Japanese Patent Application Laid-Open Publication No. 2013-121455 includes: an optical fiber that guides illuminating light to an emission end to emit the illuminating light to an object; optical fiber scanning means for periodically moving the emission end of the optical fiber for periodical scanning with the illuminating light emitted from the emission end of the optical fiber in a two-dimensional scanning region on the object; light source control means for generating a drive signal for driving the illuminating light to control ON/OFF of the illuminating light based on the drive signal; image signal detection means for receiving scattered light from the object to detect image signals at predetermined detection timing; and image generation means for allocating two-dimensional pixel positions according to the detection timing of the image signals and arranging the image signals on the pixel positions to generate an endoscopic image, wherein the light source control means generates the drive signal based on the detection timing of the image signals to make irradiation density of the illuminating light substantially constant in an entire area of the scanning region.
The conventional example also discloses that in conversion of a pixel (detection signal) detected by scanning in a spiral shape with the illuminating light emitted from the emission end of the optical fiber into a pixel of a raster scan system, pulsed light is emitted (and turned off) such that only one detection signal exists when a plurality of detection signals exist in a subregion assumed to be the latter pixel.